البلورات الفوتونية هي أوساط دورية قليلة الضياع للطاقة تستخدم للتحكم بالضوء يرتكـز عملهـا
على دورية قرائن انكسار الأوساط الجهرية المكونة لها.
و تستخدم لدراسة هذه البلورة نظرياً معادلات ماكسويل، غير أن إيجاد الحلول العامة لهذه المعادلات
تحليلياً أمر صعب لأننا نتعامل مع متجهات، لذلك نلجأ إلى الحلول العددية عند حساب العصابة الفوتونيـة
الطاقية PBG و معاملي الانعكاس و النفاذية.
Photonic crystals is a low-loss periodic medium with periodic changes of
refractive index, which is used to control the light.
Theoretically, Photonic crystals can be studied using Maxwell equations, but
it’s difficult to find a general analytical solution for these equations, since we
are dealing with vectors. So we resort to the numerical solutions for Maxwell’s
equations to calculate the reflection and transmission coefficients and the
Photonic band gap.
References used
Joannpoulos, J. D., Meade, D .R., Winn, N. J. (1997), “Molding the flow of light”, Internet source
Shumpert, D. J. (2004), “modeling of periodic dielectric structures electromagnetic crystals”, Internt source
Reynolds, A. L. (2000), Optoelectronics Research Group, Department of Electronics & Electrical Engineering, the University of Glasgow. “the transfer matrix method, T. M. M. computer program”, Special Corsoponding
There has been much interest in photonic and spectroscopic devices that are
useful for controlling transmission and reflection coefficients such as multilayer
thin films, photonic crystals, and various Bragg structures in the form of
molds or multilayer thin films.
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